1. Field of Invention
The invention relates to a lamp housing and, in particular, to a lamp housing for projectors.
2. Related Art
With rapid development in technologies, projectors have been widely used in various fields, from consumption products to high-tech products and even beyond. For example, they are used for projective exhibition in large-size conferences. They are also used in commercial projection screens or televisions. Therefore, immediate pictorial presentations can be made in reports.
Generally speaking, to ensure highly brightness and clear images onto a screen, high-power lamps are often used as the light source. To protect the fragile lamp of the projector from breaking, the lamp is often disposed inside a lamp housing. As consumers prefer more compact devices, projectors are also made smaller. The result is that the lamp inside the lamp housing faces the problem of difficult heat dissipation.
As shown in FIG. 1, the conventional projector lamp housing 10 accommodates a lamp 11. One side of the lamp housing 10 disposed has a heat-dissipating fan 12, and the other side has an opening 13 to circulate hot air. The lamp 11 consists of a lamp core 111 and a conic lampshade 112 surrounding the lamp core 111. Wind blown out from the heat-dissipating fan 12 flows toward the surface of the lampshade 112 to lower the temperature inside the lamp housing 10.
As shown in FIGS. 1 and 2, the air flow analysis inside the project lamp housing 10 shows that the air blown by the heat-dissipating fan 12 forms a turbulent region W on the lee side of the lampshade 112 after passing the lampshade 112. The air inside the turbulent almost does not flow. Therefore, there is barely any effect on heat dissipation on the lee side of the lamp 11. Moreover, there is an obvious temperature difference between the lee side and the wind-facing side of the lamp 11. The larger the turbulent region W is, the larger high-temperature area the lamp 11 has. The most significant consequence is shortening the life-span of the lamp 11. Therefore, how to evenly distribute wind blown out from the heat-dissipating fan 12 around the lamp 11 for improving heat dissipation and ensuring the lamp quality has always been an important issue in the industry.